When early trailers were posted online for Lincoln, the new biopic from Steven Spielberg, the consensus was that star Daniel Day-Lewis, known for the research he pours into perfectionist transformations, was finding his way into character through the voice. Day-Lewis as Lincoln sounded nasal, deliberate, a bit pleading, and surprisingly high-pitched. In instant homage, Jimmy Fallon took a clip from the trailer—the president, urging a group of black-clad 19th-century men sitting around a table to make a change “now, now, NOW!”—and redubbed it as Pee-wee Herman.

Compare Day-Lewis’s alien timbre to the ease of Henry Fonda, finding one of his first great film roles in director John Ford’s research-free Young Mr. Lincoln (1939). Fonda played the future president during a fictionalized period in his youth, when he grew from a bumpkin into a knowing Illinois lawyer on his way to being a visionary. Fonda’s natural voice was low and slow, a somber yet boyish drawl, with a plausible pinch of gravitas, a useful and unforced “golly gee” quality, and a likable Nebraska twang (being Midwestern then didn’t mean you sounded accent-neutral, like a newscaster).

In Young Mr. Lincoln’s most memorable scene, Abe stands before a vigilante mob and talks it down from killing a man. This isn’t easy. Abe has to try every kind of rhetoric he can think of. It’s not clear he’ll succeed or even that the mob will spare him. The crowd finally steps back, and Abe, having stopped a murder, can go on to seek justice through the law. It’s a civic triumph—though the audience, aware and grieving because of what lies ahead, mostly wishes it could protect him, too.

Fonda mesmerizes in this scene, but he’s not just a star casting a glow. His face is a window onto the weighing of imperfect options followed by the working up, and the keeping up, of courage. Devin McKinney’s new biography, The Man Who Saw a Ghost, takes Fonda’s Lincoln as a touchstone for the actor’s next four decades of stardom. The themes of his movies—and later, the almost presidential-family-level scrutiny that attended the goings-on of his iconically rebellious kids, Jane and Peter—would track closely with the youth (late 1930s), sturdy middle age (1950s), and jittery doubts (1960s) leading to the grouchy, disheveled decline (late 1970s) of America’s liberal consensus. This should be a history we know all too well, in other words. Maybe. But if the wide appeal of Mad Men’s reductive paradigm is a sign (before the 1960s: elite-dictated taste plus thrifty mass dreariness and the invisibility of all but starched white men; after the 1960s: liberated taste, social inclusion, and pop and color), our sense of cultural history may be leaving a few things out.

From the Mad Men point of view, Fonda starred in long-ago dramas set in the political world, in courtrooms, during wars, and on the frontier, movies that, with their focus on men (always men) debating or fighting it out in the West or even sometimes trying to find a sense of quaint-sounding rectitude, can seem to hail from an impossible time before. Onscreen, though, Fonda was helping to update America’s code of honor, adding important new entries under tolerance and the rule of law. While he could occasionally veer into sanctimony, what’s most amazing—as they used to say of Ginger Rogers dancing backward in high heels—is that persuading was usually secondary, and he did it while staying an artist first, complicated and exciting to watch. Far from being prehistoric, that’s work we should be so lucky to have today.

A big theme in McKinney’s book has to do with remembering the past, the way Fonda’s store of remarkable inherited experience, and his family’s stoic, repressed, duty-minded temperament, made all the things that had happened to him—and some of the harsh things that had happened along the way to America—stay close at hand, shadowing him. Centuries before Peter Fonda dropped acid with the Beatles or Jane Fonda was photographed atop a North Vietnamese tank, the Fonda family was already interesting. Genoese Fonda ancestors led a mini-revolution against a princedom, later fled to Calvinist Amsterdam, and were among early Dutch settlers in the U.S. In 1780, a New York forebear was scalped in a joint British–Mohawk Indian raid, a detail that lent tension to Drums Along the Mohawk, a Ford-Fonda collaboration set in the same region and era. During the Civil War, Fonda’s grandfather was charged with speeding the message to Union generals that Robert E. Lee was advancing to Gettysburg.

The Fondas moved to Nebraska and had become Christian Scientists by the time Henry arrived in 1905. Henry revered his parents, though Jane would note her grandfather’s melancholy; later on Henry realized how hard it had been for his father to be liberal in conservative environs. The family’s quiet social conscience led to an upsetting incident in Fonda’s youth with possibly “Rosebud”-like emotional staying power, which McKinney under- and overplays by withholding it until the end. One night, Fonda related in later interviews, when he was 14 years old and finishing up at dinner, his father took him into town. From the window of his father’s printing shop, the two watched as a large crowd torched the courthouse. The reform mayor barely escaped. The black man the crowd was chasing, accused by a white girl of rape, didn’t. Young Henry saw this man get beaten, lynched, and shot, the body dragged and burned to ash as onlookers cheered.

What effect this had is hard to say precisely. But after putting in time in idealistic small theater, Broadway, and Hollywood, Fonda slowly started to become famous for playing men of conscience. This was a type with far more variety than you might think. Sometimes, he was a dirt-poor witness to injustice, skeptical with good reason to be skeptical. Working with Ford again in The Grapes of Wrath, as the Okie scion Tom Joad, Fonda utters lines of mystically tender radicalism that the modern movie audience would be allergic to. Yet for decades this was one of the most famous speeches in film.

Other times, Fonda was a sane cowboy bystander to a vengeful posse (The Ox-Bow Incident) or a middleman decently shielding underlings from abuse (Mister Roberts). He was also capable of playing a smug example of how not to use authority (the Custer-like lieutenant in Fort Apache). In the jury drama 12 Angry Men (a film he produced), Fonda is starchy as broad-minded juror No. 8, leading those less wise to the truth. Self-superiority was a risk with the man of conscience, and Fonda was not free of sin; on the other hand, America was probably a better place for the film’s famous lesson not to rush to judgment.

Fonda’s personal life, meanwhile, was a land of pain. A second marriage (in all there were five) to Frances Brokaw, the fragile Canadian socialite mother of Jane and Peter, suffered from her depression and his affairs, plus his decision to leave the family and serve in naval intelligence during World War II. (Near the war’s end, without fully grasping what was coming, he helped give a weather briefing to the crew of the plane that dropped the bomb on Hiroshima.) Brokaw eventually checked in to a sanitarium and, like a tragic stereotype of her era’s thwarted womanhood, committed suicide in 1950. It’s not unusual for a star’s private life to diverge as far from the idealized image as Fonda’s ended up diverging, but his seems unusually sad, and oddly distant at the same time, which may be part of the point.

McKinney spends too little time probing one of the more pressing questions about Fonda today: Given the top-tier stardom he once enjoyed, why isn’t he better remembered? The obvious answer—that old cinema, especially in black and white, tends to strike young people as a turtle-paced beta version of the art form now known as movies—is true but insufficient. Other old stars—Cary Grant and James Stewart, to name a couple—are better remembered. One factor may be that despite a perfect yin-yang union with Barbara Stanwyck in the classic screwball The Lady Eve, Fonda did fewer comedies than he should (and could) have. He also partnered with women onscreen less glamorously than Grant or Stewart, both of whom got to work with Alfred Hitchcock in witty capers with gorgeous designer-clad co-stars, whereas Fonda starred in Hitchcock’s gray, guilt-ridden The Wrong Man.

Across the decades, Fonda would play the president four times. The plot of two more films turned on whether he’d be elected president and whether he’d be confirmed by the Senate for secretary of state. A telling instance of the fantasy that Fonda could somehow lead the nation was his 1976 cameo on the feminist Norman Lear sitcom Maude. With the pretend lure of mounting his one-man show (a hit about the liberal hero attorney Clarence Darrow), Maude tricks Fonda into coming into her house. When he gets there (applause), she springs her real plan: to draft him to run for president. Appealingly, he scrams. But with 1970s liberalism’s gift for snatching earnestness from the jaws of likability, it turns out that the point of the plot is not Fonda but Maude’s mental instability. Pioneering discussions of bipolar disorder ensue.

The kind of film that wore liberal values on its sleeve enjoyed a last heyday in the 1970s and started to peter out, not just because American politics grew more conservative under Ronald Reagan but because liberals too, led by the pro-fun, anti-pretension taste-making of film critic Pauline Kael, knew it had overstayed its welcome. At their convention this past August, Republicans learned the cost of selling politics with a Hollywood legend’s good word. It’s interesting to note how Clint Eastwood’s career arc—from son of a bitch to conservative holy man—has unfurled like Fonda’s in reverse. Eastwood’s star-making spaghetti Western role, the Man With No Name from A Fistful of Dollars, was originally offered to Fonda’s agents, who rejected it out of hand. He did finally team with director Sergio Leone on Once Upon a Time in the West as an aging killer named Frank. In his first scene, Frank ambles into view far from the camera, his coat swinging low like a vampire’s cape, and shoots a family dead. Once upon a time indeed. Of his Abe Lincoln role, Fonda said to the director Lindsay Anderson, “To me it was like playing Jesus Christ or God.” Of his turn as Frank, he recalled Leone’s drive to shock the audience: “Jesus Christ … it’s Henry Fonda!”

If McKinney takes for granted how well Fonda is still known, he’s right that Fonda should be remembered. Full movies are highly recommended, of course, but for those not yet familiar, there are some delicious appetizers on YouTube. To name a few of many, there’s an inexplicably riveting scene from John Ford’s My Darling Clementine in which Fonda as Wyatt Earp emerges from his trip to the barber; this is a good place to see Fonda’s lithe, skinny-legged walk—a walk that McKinney notes made James Baldwin see the actor as a kind of kindred black man. Then there’s the scene in The Ox-Bow Incident when, face behind a hat brim, he slowly reads aloud the goodbye letter of a man killed by vigilantes. For a fascinating downer, there’s the scene in Fail-Safe where President Fonda, in a secret event room in the bowels of the White House, realizes it’s all over. An American bomb launched over Moscow by accident can’t be stopped. The heavy-hearted choice Fonda’s president makes would be ludicrously untenable today. But there may be no better screen memento of the 1960s terror over the nuclear issue—or of the hell of being president.

YouTube is missing one essential Fonda moment: the Tom Joad speech from The Grapes of Wrath. It comes near the end, after the Joads have been kicked from place to exploitive place, along with thousands of migrants fleeing the Dust Bowl for Depression California. Wanted again by the law, Tom has to hit the road. This time he has a vision, though.

I’ll be all around in the dark. I’ll be everywhere. Wherever you can look, wherever there’s a fight, so hungry people can eat, I’ll be there. Wherever there’s a cop beatin’ up a guy, I’ll be there. I’ll be in the way guys yell when they’re mad. I’ll be in the way kids laugh when they’re hungry and they know supper’s ready, and when the people are eatin’ the stuff they raise and livin’ in the houses they build, I’ll be there, too.

Jane Fonda, whose acting has usually been more reliable than her commentary, said that from this scene she learned what a soul is. She has a point.